Funding for this research was provided by:
Canadian Food Inspection Agency
Received: 2 October 2017
Accepted: 26 February 2018
First Online: 2 March 2018
Ethics approval and consent to participate
: The collection of blood samples from horses in the state of Rio de Janeiro, Brazil was approved by the Ethics Committee on Animal Research of the Federal Rural University of Rio de Janeiro (COMEP / UFRRJ), under process number 23083.001257/2012-53 (protocol number 201/2012). Collections of blood from horses located in Canada and the United States were approved by the University of Saskatchewan Committee on Animal Care and Supply and by the NVSL/Center for Veterinary Biologics Institutional Animal Care and Use Committee, respectively.
: Not applicable.
: The authors declare that they have no competing interests.
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